Shareholders' Equity - Additional Information (Details) - shares	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Partnerships Exchangeable Units
Stockholders Equity [Line Items]
Exchange of partnership exchangeable units for RBI common shares (in shares)	3,294,968
Restaurant Brands International Limited Partnership
Stockholders Equity [Line Items]
Partnership exchangeable units economic interest	34.80%	35.70%
Partnership exchangeable units economic interest, shares	162,212,231	165,507,199